Service Advisor refusing to lodge a warranty claim

I purchased my vehicle in April and took it in for the first service on the 16th of September, The service Advisor Kelly Milton informed me that the thermostat is leaking, I requested that she lodge a claim from the warranty covered by M-Sure and I would cover the short fall, she agreed to this and advised me that she sent pictures to M-Sure. On the 23rd of September I called M-Sure to follow up on the claim, to my surprise M-Sure couldnt trace a claim against my policy number. I've called Mercedez Benz Constantia Kloof to raise a complaint with the dealer principal but was referred to Nomsa who is yet to get back to me with valid feedback. The level of incompetence and lack of after sales customer service is concerning for such a prestige brand,